PRS' nomenclature can be confusing.I considered the HXDA 20 head for a bit. I love Hendrix type clean and overdriven tones in general (not so much the fuzz type stuff) but yeah, I thought PRS's take on a Marshall era of sound was very interesting!
The HXDA is actually a clone of Duane Allman's actual "Live at the Fillmore" amp. There were 100, 50 and 30 Watt versions, all with EL34s. It's different from the current HRDX model.
The backstory is that when the Allman Brothers were still touring, they endorsed PRS amps, and knew where Duane's old amp was, hence the "DA". They let PRS take it apart and clone it.
The "HX" part was because PRS got hold of one of Eric Johnson's Superlead Plexis that was a Hendrix style amp, and upon taking it apart, discovered that it was the same circuit as Allman's Superbasswith only a few different parts.
So they added three switches that let you progressively go from one to the other. Makes the amp even more versatile, as you might imagine.
The HXDA is different from the HDRX amp, which is based on a clone of one of Jimi's Plexis that was modded by a guy in LA.
The HXDA was one of PRS' handwired CAD amps; the HDRX amps are circuit board amps, and have a different feel. Not that there's a thing wrong with circuit board amps, I have a couple I love, but there are a few minor differences in how they sound v handwired .
Of course, one person's "minor differences" is another person's "I can't live without those tiny differences."
Guilty as charged, your honor.